Low
d.01 on Vaillant ecoFIT Pure 835

Your boiler is continuing to run its internal pump after the heating has switched off to cool down the system, which is a normal operating status rather than a breakdown.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Pump overrun in heating mode

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 29.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that at least one radiator valve is fully open to allow water to circulateWait for the pump to stop automatically after the programmed overrun time (usually 5-10 minutes)Ensure the room thermostat is not set right at the current room temperature, causing the boiler to cycle on and off frequently

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